Regular polygonal transport containers for tetrahedral objects



Sept. 29, 1970 I. L. CARLSSON. ET AL REGULAR POLYGONAL TRANSPORT CONTAINERS FOR TETRAHEDRAL OBJECTS Filed Jan.

INVENTORS INGE L.CARL$$ON KNUT G.V. LYDIG ATTORNEY United States Patent Q Int. Cl. Bsd 5/02, 71/00 US. Cl. 229-37 8 Claims ABSTRACT OF THE DISCLOSURE Regular polygonal transport container for tetrahedral objects and the blank therefor which has integral base fins secured in position by integral retaining flaps therebetween to prevent collapse of the base fins.

This invention is concerned with a regular polygonal transport container for tetrahedral objects, consisting of a material that is capable of being folded, such as cardboard or millboard, and having both side walls, which together form a container space for the objects, and a straight pyramid-shaped bottom portion connected to the lower part of the side walls, which bottom portion protrudes into the container space, each base edge of the walls or panels of the pyramid-shaped bottom portion being adjacent to a side wall of the container.

Tetrahedral objects, for instance tetrahedral packages of the kind that are produced by successive sealing off and division of a circular tube, are often packaged together for transport and display in containers that have a pyramid-shaped bottom portion attached to the side walls. Such transport containers have generally been the hexagonal type, since the most usual tetrahedral packages have a suitable side angle for this type of container. When tetrahedral packages are packed into hexagonal containers, the units are piled in layers, each of which contains six tetrahedral packages. A further description of the pile pattern as well as the essential shape of the transport container is to be found in Swedish Pat. No. 175,387. This method of piling tetrahedral packages into hexagonal containers has been found to be both a space saver and to be satisfactory from the point of view of strength, since the tetrahedral packages in the pile configuration mutually fix one another in the pile configuration and prevent the sharp point of a tetrahedral package being directed toward the side wall of the adjacent tetrahedral package.

It has however been found in instances where the transport container is made of cardboard or millboard or similar material, that the pyramid-shaped bottom is not capable of supporting the tetrahedral packages piled into the transport container. This has resulted in more expensive material having to be used for the transport containers, and this not compatible with the manufacture of transport packaging of the throw-away type, which is principally considered here.

Reinforcement of the pyramid-shaped bottom portion, in the form of fin-shaped components alfixed to the underside of the bottom portion, has for this reason been suggested. Such reinforcement has not however solved the problem.

It is however desirable that it should be possible to produce transport packaging of the throw-away type, and the choice of material has therefore for economic reasons been restricted to corrugated cardboard and similar comparatively inexpensive material. For the same reason, the construction should in addition be simple to produce. This can be achieved by the container blank being made in one plece.

The transport container made in accordance with the invention provides a solution to both the problem of producing a simple throw-away type container from corrugated cardboard or similar material that is capable of being folded, without extra expenditure, and to that of providing a strong and rigid bottom portion for this, and the invention is characterized by the pyramid-shaped bottom portion having both base fins that are attached along the side edges of the panels abutting on one another, and also retaining flaps that are attached to the panels at an angle to that side of the appropriate panel which is turned away from the container; and by some portion of the said retaining flaps bearing onto one or more base fins, by which means the retaining flaps together fix the base fins in a mainly vertical position.

By virtue of the fact that the pyramid-shaped bottom portion is made with retaining flaps in the way specified above, the transport container is also reinforced diagonally and a more stable container is obtained.

The invention is also concerned with a blank of cardboard, millboard or similar material that is capable of being folded, for the production of a transport container, and the blank exhibits trapezoidal, interconnected, mutually identical side wall panels, and is characterized by the side wall panels along each of their longer parallel boundary lines being connected to a trapezoidal bottom panel that is bounded both by retaining flaps which by means of fold lines are connected to the bottom panels and are each bounded by a free edge and by perforations through the blank extending from this edge, and along its nonparallel edges by fold lines, by means of which the bottom panels are connected to mainly triangular fins situated between the panels, each of which fins has a central fold line.

A constructional form of the invention will be described below by reference to the attached diagrammatic drawing, on which FIG. 1 shows a blank for the production of the transport container,

FIG. 2 shows a cross section of the transport container, and

FIG. 3 shows the base of the transport container.

The blank for the production of the transport container in accordance with the invention, shown in FIG. 1, is in this constructional form assumed to be of corrugated cardboard or similar, comparatively stiff material which is however capable of being folded. The blank as a whole has a rectangular or slightly arched shape and exhibits six similar, mainly rectangular or trapezoidal side wall panels 1, which along fold lines 2 are each connected to the trapezoidal bottom panels 9.

The bottom panels 9 are further mutually connected to one another by means of the panels 11 which are to form the base fins, the panels being similar and being connected, to one another in sets of two along fold lines 6, and to panels 9 along fold lines 4.

Bottom panels 9 are further each provided with a retaining flap 8 that is connected to the appropriate bottom panel by means of a fold line 3 which extends along the whole width of panel 9, parallel to the base of the trapezoidal bottom panel, which is fold line 2. The respective fold lines 3 thus meet at their ends each of the fold lines 4. Bottom panels 9 are thus wholly delineated by fold lines 2, 3 and 4. Along fold lines 4, between fold lines 3 and the free edges 13 of retaining flaps 8, the blank has been cut through, see reference 12, retaining flaps 8 being thus capable of being folded about fold line 3.

The blank further has holes 5 in the areas where the converging fold lines 4 meet, which holes may be circular as in the case illustrated, but it is naturally also possible to give these holes another shape. Holes are situated so that they extend over parts of two adjacent bottom panels 9 and intermediate bottom panels 11, while on the other hand they do not extend into side wall panel 1.

When the blank as shown in FIG. 1 is to be made up into a transport container in accordance with the invention, the two shorter side edges of the blank are first joined by means of glueing or stapling along joint panel 7, after which bottom panels 9 on the mainly tubular body thus obtained are folded up into the space formed by the side walls 1 and are fixed in a position as shown in FIG. 2. When bottom panels 9 are folded in to the position where each bottom panel forms with the adjacent side wall 1 an angle that is on the whole the same as the side angle of the tetrahedral bodies which are to be piled in the transport container, the base fin panels 11 connected to one another in sets of two are at the same time folded towards one another to form base fins whose outer supporting edges 6 are to lie in a plane common to all the supporting edges, such plane being coincident with a plane through the lower side edges 2 of the sides of the container. These base fins 10 are then fixed in a mainly vertical position by retaining flaps 8, by virtue of the fact that these are folded about fold line 3 in a direction towards the outside of the bottom of the container. The nonparallel edges of the trapezoidal retaining flaps 8, which are made up of perforations 12, will thus bear against and support the triangular panels 11 of the base fins 10. Retaining flaps 8 thereby lie at an angle with the underside of the respective bottom panel 9, see FIGS. 2 and 3. Since base fins 10 are fixed by retaining flaps 8 in their vertical position, they prevent the bottom portion of the transport container collapsing and being pushed out to the original mainly tubular shape when the container is filled with tetrahedral bodies, or when the bottom portion for some other reason is subjected to considerable pressure.

The bottom of the erected and secured transport container, as shown in FIG. 3, has in it holes 5 which are so arranged as to their shape, size and position that the upper corners of another transport container of the same type can easily be fitted into these holes 5, the two transport containers being thus effectively affixed to one another in the lateral direction, which means that a pile of transport containers placed one on top of the other have a greater lateral stability which may for instance be made use of by more containers being piled on top of one another.

A requirement that the upper corners of a transport container should be capable of being inserted into the holes 5 in a similar container is that side walls 1 should lightly slope inwards towards the top, so that the outer circumference of the upper edge of a transport container is somewhat smaller than the corresponding circumference of the bottom portion. This is illustrated in FIG. 3 where the circumference of the upper edge of a container is indicated by a chain line.

Since panels 9 and 11, which form the bottom, need not be affixed either to one another or to side wall panels 1, the carton is easily erected by forming the Hat blank that has been joined along joint panel 7 into a tube with a hexagonal cross section-that is if the blank has six side panels-after which bottom panels 9 are pressed into the tube, whereupon they automatically take up a stable configuration with the panels 11, which are to form the base fins, being folded together to form the base fins 10 after all retaining flaps 8 have been folded out and have assumed their retaining positions against base fins 10.

The invention is naturally not restricted to only the constructional example described above, but may be varied within the framework of the following patent claims. The transport container may thus have a different member of side walls from that described and shown in the constructional example, the numbers of bottom panels 9, retaining flaps 8 and panels 11 forming the base fins, also being different. The size and outer shape of the transport container, which latter is a function of the number of side walls, are dependent on the side angle and volume of the tetrahedral packages that are to be packed into the transport container. Furthermore, retaining flaps 8 need not extend along the whole width of the bottom panel 9, but may be provided only in the areas next to the panels 11 which are to form the fins, by which means bottom panels 9 are given a larger area and thus a larger supporting surface for the tetrahedral packages piled into the container. It has been stipulated that the transport container described above should be made of corrugated cardboard, but it is naturally possible to use other materials the properties of which satisfy the requirements as regards strength, sensitivity to damp, etc., which in individual cases are set for the container.

That which is claimed is:

1. A regular polygonal transport container for tetrahedral objects comprising: a plurality of side walls connected together to form a space for objects, a pyramid shaped bottom portion connected to the lower portion of said side walls and having a plurality of panels, base fins connected to said panels and projecting upwardly into said container and retaining flaps connected to said panels and bearing against said base fins to maintain said fins in substantially vertical position.

2. The structure of claim 1 wherein said retaining flaps on each panel bear against two adjacent base fins.

3. The structure of claim 1 wherein an opening is formed at the intersection of each adjacent panel in said bottom portion.

4. The structure of claim 3 wherein said side walls taper slightly inward from the bottom of said container to the top of said container whereby a plurality of containers can be rested one on top of the other.

5. The structure of claim 4 wherein the number of side walls and panels is six.

6. -A blank of packaging material for a regular polygonal transport container that is capable of being folded comprising: a plurality of interconnected trapezoidal mutually identical side walls, a plurality of interconnected mutually identical bottom panels, each of said side panels being connected to a bottom panel along a fold line, base fins connected to adjacent bottom panels and a retaining flap connected to each of said bottom panels on the side of said bottom panel away from said side wall.

7. The structure of claim 6 wherein said base fins are triangular shaped.

8. The structure of claim 7 wherein said blank is perforated at the intersection of each of said side walls, bottom panels and said triangular shaped base fins.

References Cited UNITED STATES PATENTS 1,506,587 8/1924 Hunt. 1,587,038 6/1926 Sandor. 2,345,646 4/ 1944 Williamson. 3,000,496 9/1961 Larson.

FOREIGN PATENTS 489,127 1/1954 Italy.

DAVIS T. MOORHEAD, Primary Examiner U.S. Cl. X.R. 206 

